[SOLVED] PCIe slot question

Auchhior

Commendable
Oct 12, 2020
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Currently my graphics card (Gigabyte 1080 Windforce) is in the 2nd PCIe slot, when I originally put the PC together, I checked the manual and it didn't state anywhere that there was a bandwith difference between the first and second PCIe slot and when I checked it again right now I still couldn't confirm that there was or wasn't a bandwidth difference, but I wanted to confirm that it won't be an issue. I'll be adding a NVME SSD(Seagate Barracude 510) and wanted to see if I needed to swap PCIE slots for the GPU. In the same vein, I'm worried about the SSD temps, since it will be right above the GPU and the GPU will exhaust hot air right onto it.

parts list: https://pcpartpicker.com/user/Auchhior/saved/R4n6D3
 
Solution
The top x16 slot is the only one that can give your GPU the full 3.0x16 bandwidth, the bottom x16 looks like it only has the pins for x8 max.

I have an NVMe SSD (SN750) tucked between my GPU and 212 EVO HSF and the highest temperature it has reached since the last time I reset my HWInfo stats is 42C with a room temperature of about 30C.

In general, NAND chips prefer warmer temperatures for operating lifespan since it lowers barrier energy for write/erase, which reduces wear. You only need enough cooling to prevent thermal throttling on the controller. You need to operate NANDs at 85+C to reduce their data retention to less than one year, which shouldn't be a problem for an operating drive that can periodically do block walks and...

Zerk2012

Titan
Ambassador
Currently my graphics card (Gigabyte 1080 Windforce) is in the 2nd PCIe slot, when I originally put the PC together, I checked the manual and it didn't state anywhere that there was a bandwith difference between the first and second PCIe slot and when I checked it again right now I still couldn't confirm that there was or wasn't a bandwidth difference, but I wanted to confirm that it won't be an issue. I'll be adding a NVME SSD(Seagate Barracude 510) and wanted to see if I needed to swap PCIE slots for the GPU. In the same vein, I'm worried about the SSD temps, since it will be right above the GPU and the GPU will exhaust hot air right onto it.

parts list: https://pcpartpicker.com/user/Auchhior/saved/R4n6D3
1 x PCIe 3.0/2.0 x16 (x16 or x8+x4+x4)
1 x PCIe 3.0/2.0 x16 (max at x4 mode)
4 x PCIe 3.0/2.0 x1

From that the 2nd slot just runs @ X4 speed so you should be using the top.
 
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InvalidError

Titan
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The top x16 slot is the only one that can give your GPU the full 3.0x16 bandwidth, the bottom x16 looks like it only has the pins for x8 max.

I have an NVMe SSD (SN750) tucked between my GPU and 212 EVO HSF and the highest temperature it has reached since the last time I reset my HWInfo stats is 42C with a room temperature of about 30C.

In general, NAND chips prefer warmer temperatures for operating lifespan since it lowers barrier energy for write/erase, which reduces wear. You only need enough cooling to prevent thermal throttling on the controller. You need to operate NANDs at 85+C to reduce their data retention to less than one year, which shouldn't be a problem for an operating drive that can periodically do block walks and rewrite weak blocks as-needed.
 
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Solution

Auchhior

Commendable
Oct 12, 2020
28
2
1,535
1 x PCIe 3.0/2.0 x16 (x16 or x8+x4+x4)
1 x PCIe 3.0/2.0 x16 (max at x4 mode)
4 x PCIe 3.0/2.0 x1

From that the 2nd slot just runs @ X4 speed so you should be using the top.
Okay, that sounds right. I'll swap it out next time I open the PC to clean it.

The top x16 slot is the only one that can give your GPU the full 3.0x16 bandwidth, the bottom x16 looks like it only has the pins for x8 max.

I have an NVMe SSD (SN750) tucked between my GPU and 212 EVO HSF and the highest temperature it has reached since the last time I reset my HWInfo stats is 42C with a room temperature of about 30C.

In general, NAND chips prefer warmer temperatures for operating lifespan since it lowers barrier energy for write/erase, which reduces wear. You only need enough cooling to prevent thermal throttling on the controller. You need to operate NANDs at 85+C to reduce their data retention to less than one year, which shouldn't be a problem for an operating drive that can periodically do block walks and rewrite weak blocks as-needed.
I'll be honest. I only sort of followed the info in the third passage, but I did get that the temps shouldn't be an issue. I'll do the swap and monitor the temps to make sure everything is above board.

If y'all don't mind, how did y'all tell what the slots specs were? I checked the manual and apparently didn't understand it.
 

InvalidError

Titan
Moderator
If y'all don't mind, how did y'all tell what the slots specs were? I checked the manual and apparently didn't understand it.
If you just look into the x16 slot, you can immediately see that the bottom slot only has pins going half-way through. That's a dead giveaway that the slot cannot support full x16 electrical since it is physically lacking the necessary pins to do so.
 
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